Synthesis of Functionalized Thieno[2,3‑b]indoles via One-Pot Reaction of Indoline-2-thiones with Morita–Baylis–Hillman and Rauhut–Currier Adducts of Nitroalkenes

A straightforward protocol for the synthesis of functionalized thieno­[2,3-b]­indoles by base-mediated [3 + 2]-annulation of indoline-2-thione with Morita–Baylis–Hillman and Rauhut–Currier adducts of nitroalkenes is described. Complete regioselectivity, broad substrate scope, and mild reaction conditions make this strategy very valuable. Moreover, the thieno­[2,3-b]­indoles comprising functional groups such as hydrazine and ketoalkyl moieties are amenable for further synthetic elaboration.